Gordon Brown has met Indian Prime Minister Manmohan Singh, as the Big Brother row casts a shadow over his attempts to boost bilateral relations.

The chancellor has been repeatedly asked about claims Bollywood actress Shilpa Shetty has been the victim of racist bullying on the UK show.

He has stressed that India and Britain are against "racism and intolerance".

An Early Day Motion penned by Keith Vaz calling on Channel 4 to take action has now been signed by 20 MPs.

Mr Brown, who hopes his trip will boost trade and strategic links, said: "We [Britain and India] are for countries that practise what we preach, which is a message of fairness and tolerance to all human beings," he said.

Racism 'not tolerated'

Indian finance minister Palaniappan Chidambaram has said the row had not "strained ties" between the UK and India.

But Mr Brown said the issue had been raised repeatedly with him on his trip - and it has dominated public press conferences as well as newspapers in both countries.

I don't think we should have a casual attitude to racism...We've been very tough on this issue in public and in private

The chancellor, who is widely expected to succeed Tony Blair as prime minister, said the huge number of complaints - now about 30,000 - showed that British people did not accept racism.

After meeting Mr Singh on Thursday, he went on to visit children at schools in Delhi, and women who have been helped by charity-run projects funded by the UK.

Channel 4 chief executive Andy Duncan has said that while the scenes on the reality television show were "unpleasant and not particularly tasteful" it had not been proven they were racially motivated.

But he added that it was "perhaps unfortunate" that Gordon Brown was currently visiting India and had been questioned on the subject.

Immediate investigation

Shetty has said she does not believe she is the victim of racial discrimination.

Meanwhile, House of Commons leader Jack Straw has encouraged the media watchdog Ofcom to launch an immediate investigation into the allegations.

He said it would be "risible" to only investigate once it had finished, adding: "I don't think we should have a casual attitude to racism... We've been very tough on this issue in public and in private in the past and it's important we maintain that."

Shetty, 31, is an award-winning Bollywood actress

Several MPs have said the issue has raised questions about Channel 4's funding.

Labour former minister Chris Mullin said: "The current vulgarity arising from the Big Brother programme is a classic example of the case against any kind of public subsidy for Channel 4."

The prime minister's spokesman said that the British High Commissioner has contacted the Indian government about the row, "underlining the means by which we handle these kinds of complaints".

He said it was "not a matter the [British] government itself should become involved in" and said Ofcom would consider complaints.

But he added it was a "serious issue" and could do "enormous damage".

The message had to go out "loud and clear" that Britain did not tolerate racism, he said.